He agreed any upcoming programs must take into account previous transfers of High Reliability Water Shares (HRWS) to the Commonwealth.
“There is a risk that too much water is leaving the region,” he said.
Mr Norman said there was still strong demand for modernisation projects and he hoped there would be other incentives to keep the momentum going.
“At the moment the evidence is very clear this region is under severe socio-economic stress, in terms of water leaving the region.
“We are very conscious of that, so we are trying to work toward a program where no more water has to leave the region.”
The GBCMA heads up a consortium of bodies, including catchment management authorities, Goulburn-Murray Water (GMW), Murray Dairy, Dairy Australia and government departments, in administering the scheme.
A GBCMA submission to the Federal water inquiry found negative impacts of the Basin Plan were primarily the result of buybacks, accounting for more than 50 per cent of recovery volumes.
The submission was critical of the Federal Commonwealth On-Farm Further Irrigation Efficiency (COFFIE) program.
It described it as “overly complicated” and possibly resulting in significant conflict of interest issues. In its submission, the GBCMA said 56 detailed case studies had shown water savings ranging from half a megalitre/hectare (ML/ha) to 3.6 ML/ha, with crop and pasture production increasing by up to 0.4 tonnes of dry matter/ML.